Many automotive transmissions use overrunning roller clutches to provide selective relative directional rotation between a driving member and a driven member. The overrunning roller clutches usually comprise a plurality of rollers retained in a roller cage or clutch cage which is positioned between an inner and outer race. The rollers contained in the clutch cage will effectively engage the races, depending on the direction of rotation. Different types of clutch cages have been utilized in such transmissions. One-piece clutch cages are integrally molded and adapted to be installed as a singular unit in an annular space between the races. Other clutch cages are comprised of a series of segments which are assembled and installed in the annular space between the races.
With both types of clutch cages it is important to insure that the inner and outer race are maintained in a coaxial relationship. While most clutch cages are designed to have bearing portions which act to maintain the races in this coaxial position there is a tendency for the races to shift or skew thereby moving one or the other race out of coaxial alignment. One-piece cages have been designed to overcome this problem of non-coaxial alignment. The installation of the one-piece cages into the space located between the inner and outer race, however, requires a fairly substantial simultaneous torque and thrust load, which presents ergonomic problems since one-piece cages are not perfectly round and therefore require high torque during assembly.
Most one-piece cages are now being designed to have at least one expansion joint to allow the cage to expand and contract as a result of temperature fluctuation, moisture absorption, and cooling effects resulting from operation of the transmission.
One-piece cages which have incorporated such expansion joints elastically deform during the heat cycles of the automatic transmission. However, it has been experienced that the cage expansion joints also plastically deform, thereby causing operational interference and increased frictional wear.
In cages which are comprised of discontinuous or segmented cage members, connector means are necessarily located on each segment for adjoining the adjacent cage segments. One type of clutch cage system having segmented cage members is described in U.S. Pat. No. 4,054,192, issued to Johnson which comprises a number of engaged plastic segments which fit together between the races. However, while Johnson meets the objective of holding the cages centered between the races, the individual segments have an undesirable tendency to move or dislodge in the radial, axial and/or circumferential directions.
The present invention eliminates the problems particular to the above described prior art and provides segmented cages that are securely connected to an adjoining segment.
It is, therefore, an object of the present invention to provide an improved clutch wherein a plurality of interlocking cage segments are securely engaged with each other in three directions: axially, radially and circumferentially.
It is another object of the present invention to provide an improved method for installing segmented cages into a clutch assembly by providing at least one engaging means and at least one retaining means on the segmented cage so that the interlocking segments are automatically secured in the circumferential direction. In one embodiment the segments are interlocked to form a cage using a bi-directional axial assembly method. In another embodiment the segments are interlocked to form a cage using a unidirectional radial assembly method.